import React ,{ useState }from  'react';
/**
 * 
 * @returns 
 * 当初始值和需要改变的值一样是页面将不在重新渲染
 */
function App (){
    console.log('App')
    const [title, setTitle] = useState('child');
    return (
        <>
           <div>
             <h1>learning hooks three { title }</h1>
              <button onClick= { () => setTitle(title)}>更改</button>
           </div>
        </>
    )
  
}

export default App